I think we are going to see more details,

The things i would check in order are:

Is the @hotmail address listed in the sys_user.email field?

Is the @hotmail address listed in the cmn_notif_device.email_address field?

Also click on the Email log entry you have highlighted. On the record click on the UI action that says "Show Log Entries" which should give you more details from the server logs, crucially it should show you some more debug info